Submersible long shaft pumps are a type of vertical installation centrifugal pump. Their shafts are typically quite long, ranging from several meters to tens of meters. If the concentricity alignment between the pump and the motor is not properly adjusted, it can cause a series of problems, such as excessive vibration, high noise, and in severe cases, the pump shaft may break. Therefore, the concentricity alignment accuracy of submersible long shaft pumps is required to be relatively high.
In this article, Zoomlian Pump Industry, a submersible long shaft pump manufacturer, will introduce to you the general steps for concentricity alignment of submersible long shaft pumps for your reference. If there is no professional pump repair worker on site, it is recommended to seek the assistance of technicians from the long shaft pump manufacturer for alignment.
1. Preparatory Work:
Make sure that the long shaft pump and motor are installed on a flat and solid foundation. Use a level to ensure that the base is level.
Clean the surface of the coupling to remove oil stains and impurities to ensure the accuracy of the measurement.
2. Initial Calibration:
Use a dial indicator or feeler gauge to check the radial and axial deviations of the coupling. If deviations are found, the concentricity can be preliminarily corrected by adjusting the thickness of the shims.
Ensure that the end face clearance of the coupling is between 1 and 2.5 mm to avoid vibration or damage caused by too small or too large a clearance.
3. Precise Measurement and Adjustment:
Use a dial indicator or a dedicated alignment tool to precisely measure the coupling, and record the radial and axial deviation values.
Based on the measurement results, the radial and axial deviations can be gradually eliminated by adjusting the thickness of the shims under the motor feet or making fine adjustments with a crowbar.
4. Review and Confirmation:
After the initial adjustment is completed, use a dial indicator to measure the concentricity of the coupling again to ensure that the deviation is within the allowable range (usually within 0.1mm).
If the deviation is significant, it is necessary to readjust the thickness of the gasket or use other tools for further fine-tuning.
After confirming that the concentricity meets the requirements, tighten all bolts and check whether the coupling rotates flexibly and without any metallic friction sounds.
Start the long shaft pump unit, observe its operating status, ensure there is no abnormal vibration or noise, and record the operating data for reference in subsequent maintenance.